For the beginner, Raspberry Pi is Single Board Computer (SBC) that enables more people to have access to digital computers. In other words, you can set up your computer at an affordable price. Check out the Wikipedia on Raspberry Pi for the history.
Since the launch of Raspberry Pi 3 Model B on 29th February 2016 (Birthday of Raspberry Pi), the news has gone viral, everyone wants to get this powerful single board computer. So here you are! The Raspberry Pi 3 Model B is out and it is AMAZING.
There are two huge upgrades compared to Raspberry Pi 2. First, upgrade of processor, RPi 3B is using Quad-Core Broadcom BCM2837 64-bit ARMv8 processor (RPi 2 is using a 32-bit processor), making the processor speed increase from 900 MHz on the RPi 2 to up to 1.2GHz on the RPi 3.
2nd huge upgrade (and this is the one we’re personally most excited about) is the addition of a BCM43143 WiFi chip BUILT-IN to Raspberry Pi 3B. No more WiFi dongle taking up the USB port! Yes, RPi 3B is WiFi ready. There’s also Bluetooth Low Energy (BLE) on board making the Pi an excellent IoT solution (BLE support is still in the works, software-wise).
Lastly, there’s an upgraded switched power source that goes up to 2.5 Amps instead of just 2 Amps - allowing your Pi to power even more powerful devices over USB ports.
The best part about all this is that the Raspberry Pi 3 Model B keeps the same shape, connectors, and mounting holes as the Raspberry Pi 2. The only difference is a slight change in where the LEDs are. 99% of cases and accessories will still be fully compatible with the Pi 3, Pi 2, and Pi B + - though if you have a case with a metal top, it might affect the WiFi signal. Of course, you can still use RPi casing with fan.
With the increase of processor core and speed, the CPU requires higher power and will get warmer compare to RPi 2. This Rpi casing with a fan is perfect to cool it down :)